DBU-catalyzed diastereoselective 1,3-dipolar [3+2] cycloaddition of trifluoroethyl amine-derived isatin ketimines with chalcones: synthesis of 5'-CF3-substituted 3,2'-pyrrolidinyl spirooxindoles

A diastereoselective 1,3-dipolar cycloaddition reaction between trifluoroethyl amine-derived isatin ketimines and chalcones was successfully achieved in the presence of DBU. A series of 5'-CF3-substituted 3,2'-pyrrolidinyl spirooxindoles were efficiently synthesized with high yields and excellent diastereoselectivities (up to 89% yield, and >99 : 1 dr). The in vitro anticancer activities of these highly functionalized spiro[pyrrolidin-3,2'-oxindole] derivatives were evaluated.

Dehydroabietane-type bifunctional organocatalysts in asymmetric synthesis: recent progress

Dehydroabietane-type bifunctional organocatalysts derived from rosane-type diterpenes of dehydroabietic acid (DHAA) and dehydroabietylamine (DA) have been utilized in a wide variety of highly enantioselective reactions. Since one well-documented review exclusively reported on the development of terpene-derived bifunctional thioureas in asymmetric organocatalysis in 2013, fragmentary progress on the dehydroabietane-type bifunctional thioureas and squaramides has been mentioned in other reviews. In this mini-review, we systematically analyze and reorganize the published literature on dehydroabietane-type bifunctional organocatalysts in the recent decade according to the type of catalysts. Our aim is for this review to provide helpful research information and serve as a foundation for further design and application of rosin-based organocatalysts.

Metabolomics study of the hepatoprotective effect of total flavonoids of Mallotus apelta leaf in carbon tetrachloride-induced liver fibrosis in rats

Mallotus apelta leaf, recorded in the quality standard of Yao Medicinal Material in Guangxi Zhuang autonomous region, is commonly used in the treatment of liver diseases. Total flavonoids of M. apelta leaf (TFM) had good anti-fibrosis activity, but the anti-fibrosis mechanism of TFM is still unclear. Nuclear magnetic resonance technology was used to study the dynamic changes of urine metabolites in CCl4 -induced liver fibrosis before and after TFM treatment. Ingenuity Path Analysis (IPA) was used to find potential target genes for TFM to improve liver fibrosis and verify the expression of target genes by real-time fluorescent quantitative PCR and Western blotting. TFM can significantly reduce serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) levels, improve liver steatosis and reduce inflammation; in urine metabolomics, a total of seven potential biomarkers were found, mainly involving two metabolic pathways; IPA analysis showed that TNF may be a potential target for TFM to improve liver fibrosis induced by CCl4 in rats. This study found that TNF may be a potential target gene for TFM treatment of liver fibrosis, and shows that the anti-fibrosis mechanism of TFM could improve liver fibrosis by regulating the tricarboxylic acid cycle and subtaurine metabolism.

Mapping knowledge structure and research trends of knee osteoarthritis with meniscus in two decades: A bibliometric analysis

BACKGROUND

Knee osteoarthritis (KOA) is a chronic degenerative disease that is closely related to the meniscus. Currently, no bibliometric studies have jointly analyzed KOA and the meniscus. This study aimed to provide a comprehensive analysis of the knowledge structure of KOA and the meniscus across two decades and to identify the emerging research trends from a bibliometric perspective.

METHODS

All articles reporting KOA and the meniscus from 2001 to 2021 were obtained from the Web of Science Core Collection. R software, CiteSpace, VOS Viewer, and Microsoft Excel were used to analyze the publications including the authors, cited authors, journals, cited journals, country of research, institutions, and research focus. These data were used to generate visual knowledge maps of the outputs.

RESULTS

A total of 3,218 articles were retrieved. Guermazi was identified as the author who had contributed the most to the field and Osteoarthritis and Cartilage was identified as the most productive research journal. The United States is the global leader in the field and the center for international cooperation with less international collaboration occurring in Eastern Asia. Boston University was the most prolific institution. According to the data, "articular-cartilage," "meniscectomy," "follow-up," "anterior cruciate ligament," and "cartilage" were identified as research hotspots in the field. "Consequences," "prognostic-factors," and "receptor" were predicted as future hot topics of research.

CONCLUSIONS

This study is the first comprehensive bibliometric study to jointly analyze KOA and the meniscus. Our data enable a better understanding of research trends and identify research hotspots and gaps in knowledge across the field. Our findings provide practical information for researchers to better understand the key research areas and identify the research frontiers and future hot topics.

Fe-Curcumin Nanozyme-Mediated Reactive Oxygen Species Scavenging and Anti-Inflammation for Acute Lung Injury

Pneumonia, such as acute lung injury (ALI), has been a type of lethal disease that is generally caused by uncontrolled inflammatory response and excessive generation of reactive oxygen species (ROS). Herein, we report Fe-curcumin-based nanoparticles (Fe-Cur NPs) with nanozyme functionalities in guiding the intracellular ROS scavenging and meanwhile exhibiting anti-inflammation efficacy for curing ALI. The nanoparticles are noncytotoxic when directing these biological activities. Mechanism studies for the anti-inflammation aspects of Fe-Cur NPs were systematically carried out, in which the infected cells and tissues were alleviated through downregulating levels of several important inflammatory cytokines (such as TNF-α, IL-1β, and IL-6), decreasing the intracellular Ca2+ release, inhibiting NLRP3 inflammasomes, and suppressing NF-κB signaling pathways. In addition, we performed both the intratracheal and intravenous injection of Fe-Cur NPs in mice experiencing ALI and, importantly, found that the accumulation of such nanozymes was enhanced in lung tissue (better than free curcumin drugs), demonstrating its promising therapeutic efficiency in two different administration methods. We showed that the inflammation reduction of Fe-Cur NPs was effective in animal experiments and that ROS scavenging was also effectively achieved in lung tissue. Finally, we revealed that Fe-Cur NPs can decrease the level of macrophage cells (CD11bloF4/80hi) and CD3+CD45+ T cells in mice, which could help suppress the inflammation cytokine storm caused by ALI. Overall, this work has developed the strategy of using Fe-Cur NPs as nanozymes to scavenge intracellular ROS and as an anti-inflammation nanodrugs to synergistically cure ALI, which may serve as a promising therapeutic agent in the clinical treatment of this deadly disease. Fe-Cur NP nanozymes were designed to attenuate ALI by clearing intracellular ROS and alleviating inflammation synergistically. Relevant cytokines, inflammasomes, and signaling pathways were studied.